Apis motorglider
key
its performance and handling like? Any problems to watch out for?
Thanks,
Key
Darryl Ramm
JJ making fun of you for flying a motorglider.
Darryl
Morgans
> "Darryl Ramm" <darry...@gmail.com> wrote
> JJ making fun of you for flying a motorglider.
Perhaps, but when there are no active glider operations close by, being able
to go fly when you want to, where you want to, not having to drive a couple
hours to fly, without having to depend on finding someone to give you a lift
up, a self launching glider makes a bunch of sense. It is the way I'm
probably going to have to go.
--
Jim in NC
Mark Jardini
Mark
Mark Jardini
aircraft.
First, the aircraft is built very well with a lots of attention to
detail.
Cockpit is very comfortable but it is tight and could be longer in the
trunk area. I am 6ft and OK. Plenty of leg room. Plenty of width.
Panel is DG style and enough room for 7x 2-1/4 size instruments.
Rigging is fiddle-ish. I have not managed it without at least a
modicum of help. If you are going to fly alone, you will need a remote
control self rigger to move things about.
The trick is that the wings need to be in anhedral to fit into the
drag pins, then the tips come up to align the mains.
Derigging is quick. I timed myself from taxi to trailer through
driving away at 40 minutes.
Avionic is a very good trailer.
The engine installation is the crown jewel of the aircraft. Just
beautiful. The 447 is a tried and true powerplant. I have never had
trouble with starting or relights, and I make it a point to do one
relight a flight even if I don't need it. The only issue I see is that
the toothed belt driving the prop is sealed inside the mast. No way to
change it. I hope is lasts a long time......
I get generally 500fpm. The engine should be turning 6000+ rpm's and I
get only 5800 so I think the factory prop is too coarse in pitch, but
I am not ready to change it yet.
Also the engine temp runs very cool, rarely getting above 180C even on
hot days. Good for longevity but I think that there is a lot of power
there still not being utilized. By lb/hp it should do better. I am
Still messing with the carburetor. I am roughly getting 1000 ft per
liter of fuel.
I have recently put turbulator zigzag as recommended at 65% MAC and
that dropped 3 kts off thermaling speed. 30 deg bank and 40kts.
I think the rudder needs turbulators as well. Rudder forces at low
speeds are initially high, then release giving more yaw than you asked
for. Feels like I am pulling a high drag bubble. It swims in yaw a bit
in cruise as well. That should be correctable. More to come.
Flaperon forces are high. You are pushing a big wing through the air.
I climb with most anything, Run is not bad up to 80kts. The trim is
unsatisfactory. It is a simple spring arrangement. (I was spoiled by
Glasflugel's push button trim). You can adjust it for enough back trim
or enough forward, but not both. The elevator has a deep recurve on
the trailing edge, so the stick forces go up with airspeed. At
redline, the forward pressure is prodigious. I don't think I will fly
in that speed range often though.
That is all that comes to mind. Questions or comments?
Mark
Andy
>The trick is that the wings need to be in anhedral to fit into the
>drag pins, then the tips come up to align the mains.
Similar adjustment required to rig any modern glider. With a fixed
height one man rigger the adjustment can be easily made with the
trailer ramp jack. Raising and lowering the fuselage is the same as
lowering or raising the wing tips but it has the advantage that you
can monitor the alignment while you make the adjustment.
>The only issue I see is that
> the toothed belt driving the prop is sealed inside the mast. No way to
> change it. I hope is lasts a long time......
Can the belt be inspected? How is it replaced?
Andy
Mark Jardini
Avionic does not have a "jacked ramp". The cradle has an over center
cam that lifts the aircraft off its main wheel. Agreed, the jack would
be better for rigging purposes.
The belt can be seen and inspected through it s length. The center
portion of the mast is enclosed trapping the belt within by some mid
shaft cross sectional enclosings. I can only assume this is one of
those fiberglass impregnated toothed belts they use in cars that last
60k miles.
My guess would be you send the mast back to be opened and reclosed or
you buy a new one.....
Mark
Darryl Ramm
And for those Cobra trailers with hydraulic jacked ramps and heavy
motorgliders, I'd rather trust the hand cranked gears in my one-man
rigger or the person holding my wingtip than trust the hydraulic jack
with the weight of my motorglider while tweaking the jack height. I
slide in a triangular wooden block as a safety device under the ramp
scissors. If the jack fully collapses, I don't think the jack has the
leverage to jack up mu ASH-26E again.
Darryl
5Z
ASH-26E. And to keep the wings at a comfortable height, that means
it's operating near the bottom of its range. Really nice during
disassembly to have one hand on the jack and the other on a main pin,
then slowly lower the fuselage until the pin starts to rotate.
I did disassemble the jack assembly recently to replace an O ring in
the jack. The base plate was warped due to the horizontal force being
applied to lift the glider from a completely lowered jack.
Straightened it out in a hydraulic press, and might try to reinforce
it next winter, but it will likely last another 5-10 years if I do
nothing.
-Tom
Eric Greenwell
> And for those Cobra trailers with hydraulic jacked ramps and heavy
> motorgliders, I'd rather trust the hand cranked gears in my one-man
> rigger or the person holding my wingtip than trust the hydraulic jack
> with the weight of my motorglider while tweaking the jack height. I
> slide in a triangular wooden block as a safety device under the ramp
> scissors. If the jack fully collapses, I don't think the jack has the
> leverage to jack up mu ASH-26E again.
>
my ASH 26 E. It has no problem raising the fully assembled glider from
the bottom to the height needed to lower the gear. I've done that for
over 400 rig/derig cycles.
--
Eric Greenwell - Washington State, USA (netto to net to email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz
Bob Luten
I've been building an Apis M from a kit purchased 4-5 years ago from
AMS-Flight. I obtained an amateur-built airworthiness certificate
last summer and flew it as a pure glider, and promptly "bent it" a
little -- I'll come back to that.
Let me address the issues I've come across over the several years of
putting the glider together, and visiting the factory (both AMS and
Pipistrel) several times.
(1) The 447 installation has been problematic, for all concerned. So
far as I know, only 3 with that configuration were delivered by the
(AMS) factory. One, a kit put together by Jack Lurowist (deceased),
did not go together at all well -- there were major vibration
problems, confirmed in a factory-built ship by Paul Yarnell. As best
I was able to determine, the issues were mostly due to the inherent
vibration of the 447 and inadequate shock mounts (at the mast/fuselage
hinge), a lack of torsional rigidity in the carbon propeller mast, and
propeller balance and/or symmetry issues. The sealed mast was one of
the factory "fixes" and apparently cured the torsional rigidity
problem. The recommended belt (which I understand to be essentially a
Harley-Davidson belt) replacement procedure is to cut, with a Dremel,
the epoxy/tape that bonds the belt cover to the carbon mast, and then
rebond/tape it when done with the belt replacement. One of the
results of the excessive vibration was that the exhaust system
developed cracks with a very few hours of operation. I've been told
that the factory fixes (replacement rubber shock mounts, bonding the
belt cover to the mast, and a redesigned propeller) essentially solved
the problems, and perhaps Mark's experience is proof of that. The
more recent fix for all the 447 problems was a complete redesign and
replacement of the propulsion subsystem; the current self-launch Apis
uses a Hirth F33 engine in a mast built up from aluminum plates,
hinged on an entirely different lamination bonded into the upper
fuselage immediately in front of the mast door opening.
(2) My experience with flaperon forces is a bit different from
Mark's. The problem in my fuselage, and apparently many others, was
misalignment of the flaperon bell cranks mounted on the engine
compartment sidewalls. Pipistrel has redesigned those bell cranks to
incorporate a self-aligning bearing to accommodate the wing dihedral.
I'm currently in the process of replacing these bell cranks and will
insure that the bearing housings attached to the sidewalls are
precisely aligned with the flaperon hinge post axis. Another flaperon
(static) force issue discovered by Robert Mudd is the misalignment of
the several flaperon hinge posts; this misalignment, if present, can
be felt when moving the flaperon from one extreme to the other with
the glider disassembled. The flight result of my particular problems
was that the flaperons were _extremely_ stiff, and controlling the
glider on tow was a two-handed operation. I expect all these static
force issues to go away with the proper installation of the new bell
cranks. Hopefully I will discover Mark's high speed control force
issues when I get the ship flying again.
(3) Finally, my "event" (it wasn't an accident or incident, so that's
what my FSDO inspector called it) last summer. To make a long story
short, I landed in a bit of a crosswind and when my steerable tail
wheel touched down, I entered a PIO (yaw axis) and left the runway.
When I tried turning to parallel the runway, the ship yawed (to the
right) but continued straight ahead in the soft dirt, putting a
substantial side load on the main wheel. The tire peeled the right
wheel half completely off the wheel assembly bolts, fortunately with
no other damage to the fuselage. I've replaced the factory wheel (and
brake) with a Tost Tria wheel and disk brake.
BTW Mark, I've been meaning to come over and see you, and your Apis
for at least a couple of years. I. and my Apis, are in northern Idaho
during the summer.
-- Bob --
Mark Jardini
The ship and I will be in Ephrata the week after memorial day.
Mark
Ian Strachan
Mark Jardini wrote:
> The belt can be seen and inspected through it s length. The center
> portion of the mast is enclosed trapping the belt within by some mid
> shaft cross sectional enclosings. I can only assume this is one of
> those fiberglass impregnated toothed belts they use in cars that last
> 60k miles.
>
> My guess would be you send the mast back to be opened and reclosed or
> you buy a new one.....
My Nimbus 4DM syndicate has had two engine drive belt failures over
the last 8 years, one at the launch point just before the after-C of A
test flight six weeks ago. The belt was changed within a week, but
could have been quicker had we stocked a spare.
In the case of any belt-driven MG engine, there really should be a
relatively straightforward way of replacing the belt if it fails,
without rendering the engine unit unserviceable for a considerable
time. After all, preventing lands-out is the whole reason for having,
and paying for, an engine installation.
Ian Strachan
Lasham Gliding Centre, UK
key
reading this.
Key